Switch construction and method



SWITCH CONSTRUCTION AND METHOD Filed Feb. 4. 1966 Sheet of 2 80 I08 I04 2 e I 84 754 9s w \\1\ fl.4 I WA III g 1 H H J h INVENTOR. w 'll 76 FRED v. KENYON 7;; In\ I Y 100 U 92 2 H6 M 76 22 a I F v c 2 H4 HIS ATTORNEYS Feb. 25, 1969 F" v. KENYON 3,429,199

SWITCH CONSTRUCTION AND METHOD Filed Feb. 4. 1966 Sheet Z FIG-I3 FIG-l4 FIG-l5 FIG-l2 INVENTOR. FRED V. KENYON HIS ATTORNEYS 3,429,199 SWITCH CONSTRUCTION AND METHOD Fred V. Kenyon, Anaheim, Calif., assignor to Robertshaw Controls Company, Richmond, Va., a corporation of Delaware Filed Feb. 4, 1966, Ser. No. 525,049

US. Cl. 74-548 Int. Cl. F16c 1/06; H01h 9/00 3 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a switch construction and method.

One feature of this invention includes the use of an inexpensive elongated integral connector, made of resilient or plastic material, which has a tubular end to be frictionally telescoped over an end of a rotatable switch operating shaft. The connector also has an integral rod or rod-like end to be frictionally telescoped into the opening of an operating actuator or knob. The construction of the connector is such that it provides a continuously tight longitudinal sliding telescoping action with the shaft end and the actuator opening and simultaneously provides an effective torque locking engagement with such shaft end and actuator opening.

This connector is particularly useful in a combination wherein a switch means is provided with a rotatable operating shaft having a shaft end over which one end of the connector is frictionally telescoped as previously described. Such combination also includes an operating actuator or knob having an opening into which the other end of the connector is frictionally telescoped, as previously described.

The combination is such that a manufacturer, supplier, or service organization can produce such combination with a switch means having a rotatable operating shaft preassembled with such switch means. Such switch means and preassembled shaft may be produced in any desired quantities. Also various connectors may be produced in any desired quantities. If desired, such various connectors may all have the same type of tubular end, so that all of such connectors may be telescoped over all of the shaft ends of such combinations at any time, either at the factory, supply branch, or even during a service call at a users home or the like. Also, a suitable connector may be selected from a plurality of such various connectors which has its rod-like end shaped to telescope into the opening of a particular actuator or knob.

Consequently the combination of the switch means and rotatable operating shaft may be preassembled in any desired quantities with the assurance that all such preassembled combinations may be readily further combined with any of a large number of various connectors of this invention, and with any of a large number of various actuators or knobs which may have variously shaped connector receiving openings. This permits the maintenance of an efficient and versatile inventory of such preassembled combinations, integral connectors, and/or actuators or knobs.

This invention may be used by a switch manufacturer or supplier, who can supply any quantities of such preassembled combinations and integral connectors to any purchaser. The purchaser may provide and use actuators or knobs of his own design. The purchaser may also purchase actuators or knobs already made by such manufacturer or supplier, or the purchaser may purchase actuators or knobs specially made b such manufacturer or supplier for the user.

Also this invention may be used in connection with service calls where the user of a previous switch already installed on an electric range, or the like, has found such previous switch to be out of order or unsatisfactory. Such user may wish the previous switch replaced by a new switch, but desires to retain the old knob which has been tailored to harmonize with pattern of the range. Under such circumstances the service man may be provided with a preassembled switch means and shaft of this invention and with a small plurality of various connectors of this invention which have rod-like ends of knobs known to be prevalent in such locality. The service man can then replace the old switch and its shaft with a new preassembled combination of this invention, and can select a connector which has an end which can properly telescope into the users old knob. Since such connector has had its tubular end made to telescope into the shaft end of the new preassembled combination, the replacement can be readily made with a minimum of service operations.

A very inexpensive service kit may be made available to such service man, which includes the preassembled switch means and operating shaft, and a small plurality of connectors of this invention from which the proper connector can be chosen. The small plurality may be from four to six connectors that can be made very inexpensively, so that the unused connectors may be discarded, if desired.

The shaft of this invention may be provided with rupture grooves so that the shaft may be easily severed at any one desired groove to provide the desired spacing between the switch means and the actuator. Such severing operation may be performed while the shaft is on the preassembled combination.

Other features of this invention are apparent from this description, the appended claimed subject matter, and/ or the accompanying drawings, in which:

FIGURE 1 is a perspective exploded view of one embodiment of this invention.

FIGURE 2 is a cross section along the line 2-2 of FIGURE 1, with the shaft and the actuator being rotated for a better showing of the invention, and with the switch means being mounted on a panel of a range or the like.

FIGURE 3 shows the embodiment of FIGURES 1 and 2 changed by shortening the shaft, by breaking off a portion thereof, and then telescoping the connector on the shortened shaft.

FIGURE 4 is a cross section, of a portion of the actuator, taken along the line 44 of FIGURE 1.

FIGURE 5 is a cross section of a portion of FIG- URE 1, taken along the line 55 of FIGURE 1.

FIGURE 5A is an end view of the lower cam bearing in the switch casing.

FIGURE 5B is a detail view of the bushing mounting construction behind the front panel of the switch casing.

FIGURE 6 is an enlarged side view of the connector shown in FIGURES 1, 2 and 3.

FIGURE 7 is a cross section along the line 7-7 of FIGURE 6.

FIGURE 8 is a cross section along the line 8-8 of FIGURE 6.

FIGURE 9 is a side view of FIGURE 6, taken from the line 9--9 of FIGURE 6.

FIGURE 10 is a view similar to FIGURE 7, but show- 3 ing another embodiment of the inner tubular surface of tthe connector shown in FIGURES 1-9.

FIGURE 11 is a side view of another embodiment of a shaft which may be used with this invention.

FIGURE 12 is an end view from the right side of FIGURE 11.

FIGURES 13-16 are perspective views showing other forms of connectors which may be used in connection with this invention.

Certain words may be used in connection with the specification and claimed subject matter of this application indicating direction, relative position, etc. Such words are used for the sake of clearness and brevity. However, it is to be understood that such words are used only in connection with the drawings of this application, and that in actual use, the parts so described may have entirely different direction, relative position and the like. Examples of such words are vertical, horizontal, upper, lower, etc.

The word far is sometimes used in the specification and claimed subject matter to indicate that one end of the shaft, one end of the connector, and one end of the opening in the actuator may be further away from the main part of the switch casing than the near end of such shaft, connector or opening, and the like.

FIGURE 1 shows a combination 20, according to this invention, which may be used in replacing a previous combination, or which may be used as original equipment to be supplied to a user, as desired.

The combination 20 of this invention may be a combination wherein a switch means 22 has a rotatable operating shaft 24, which may have a far shaft end 26.

An actuator, manipulator or knob 28 may be operatively connected to the far shaft end 26 to rotate or rotationally oscillate the shaft 24 and to operate the switch means 22. The actuator 28 may be in the form. of a decorative knob, if desired. Such manipulator or knob may have been previously used and tailored to the original range, so that it may be desirable to use this knob in connection with the switch means 22, and the shaft 24, after such switch means 22 and 24 have been used to replace original switch on the range.

To connect the actuator or knob 28 with the far end 26 of the shaft 24, an integral connector 30 may be provided, or selected, which has a frictional tubular near connector end 32 with an inner tubular surface 34, FIG- URE 7, frictionally telescoped over the far shaft end 26, FIGURES 1-3. The connector 30 may also have a far connector end 36, with an outer surface frictionally telescoped with a connector receiving actuator opening 40, FIGURE 4, in the actuator 28. Thus the far shaft end 26 Within the connector 30 can be maintained entirely axially spaced from the manipulator opening 40.

The connector 30 may be an integral elastic connector, such as plastic conector with the inner connector end being a tubular connector end and the far connector end being a solid rod, or rod-like, end.

The connector 30 may be molded from any suitable elastic or plastic material. For example, such connector may be molded from a suitable nylon material made to retain its shape at all temperatures expected to be imposed on the connector. Also, the material is preferably such that retains a frictional and resistingly slidable connection with the outer surface of the shaft end 26, and the inner surface of the actuator opening 30. The actuator 40 may be made of any suitable material, such as a synthetic resin, of the character of Bakelite, and the like.

Preferably the shaft 24 has an outer cylindraceous shaft surface 41 with a torque transferring flattened shaft surface 42.

The near connector end 32 has a near cylindraceous inner tubular surface 34, FIGURES 6 and 7, with a torque transferring flattened surface 44, which telescopes over the outer shaft surface with torque locking engagement and frictional longitudinal sliding engagement.

The far connector end 36 has an outer cylindraceous connector surface 38, with a flattened torque transferring connector surface 46. The connector receiving actuator opening 40, FIGURE 4, has an inner cylindraceous opening surface 48 with a torque transferring flattened opening inner surface 50, closely telescoping the far connector end 36 with a torque locking engagement and with a frictional longitudinal sliding engagement.

The flattened tubular surface 44 may have a resilient longitudinal ridge means 52, which may be in the form of two longitudinal narrow and low ridges 52. Also, the flattened connector surface 46 may have resilient longitudinal ridge means in the form of two longitudinal resilient narrow and low ridges 54. The ridge means on the surfaces 44 and 46 increase the longitudinal frictional engaging etliciency between the connector surfaces an the surfaces of the shaft and actuator opening 40.

The far connector end 38 may have a far cylindrical outer connector surface 56. The near connector end 32 may have a near outer cylindraceous tubular surface 58 which is cylindrical and coaxial with the near cylindrical inner connector surface 34. That is, the near cylindrical surfaces 34 and 58 of the tubular part of the connector may be cylindrical and coaxial with each other. The far connector end 36 may have an outer cylindrical surface 56 which is of the same diameter and is coaxial with the near cylindrical outer connector surface 58.

The far shaft end 26 has a connector receiving portion longitudinally of uniform cross section between the fracture grooves 60, and this portion is of transversely irregular cross section, as is produced, for example, by cylindrical outer surface 41, and the fiat surface 42. The tubular near connector end 32 has a substantially similarly longitudinally uniform inner cross section and a substantially similar transversely irregular inner cross section so that the near connector end 32 is rotationally locked with respect to the far shaft end 26 and such near connector end 32 is frictionally longitudinally slidably removable from such far shaft end 26.

In the same manner the far connector end 36 has a longitudinally uniform cross section and a transversely irregular cross section and the connector receiving actuator opening 40 has a substantially similar longitudinally uniform cross section and a substantially similar transversely irregular cross section, so that the far connector end is rotationally locked to the actuator opening and such actuator opening is frictionally slidably removable from such far connector end.

In the embodiments shown in FIGURES 10, 11, 12, a shaft 68 has a far shaft end 70 which has a substantially square cross section. Any connector 71 that is to cooperate with far shaft end 70 may have an inner tubular surface 72 that has a substantially square cross section.

The far shaft end of both the embodiments of FIGURES 1-9 and of FIGURES 10-12 may have fracture formation means or grooves 60, at which grooves either shaft niilay be broken or shortened to vary the length of the s a t.

One of the inner sides of the inner square surface 72 may have ridge means or ridges 74 which cooperate with one of the sides of the square shaft 68. The far connector ends for the shaft 68 may be the same as the far connector ends 36 for the shaft 24. Connectors for shaft 68 are not interchangeable with connectors for shaft 24.

The switch means 22 may include a switch casing 76, with a protruding bushing 78 through which the shaft 24 or 70 extends, with the far shaft end 26 or 70 beyond the far end 80 of the bushing 78. The construction is such that the shaft 24, or 70 may extend a relatively great distance from the bushing 78, as shown in FIGURE 2, or the shaft may be fractured and its length variously reduced, even to such an extent, for example, that a portion of the near connector end 32, FIGURE 3, extends into the bushing 78, and permits the actuator 28 to be mounted very close to the range panel 82.

In either embodiment of FIGURE 2 or 3, if desired, the

switch casing 76 may be mounted with its front panel 84 against the range panel 82. The bushing 78 may be extend through an opening 86 in panel 82. A Palnut 88 may then be threaded on the outside of the bushing 78, to hold the bushing 78, and the switch casing 76 adjacent the range panel 82. The Palnut 88 may have its outer perimeter hexagonal for turning the same threaded engagement with the bushing 78.

The actual switch construction inside the casing 76 may be of any desired construction, the details of which are not material to the present invention. For example, the interior of the switch casing 76 may contain a switch of infinite variation, that is, a switch that is capable of producing a gradually varying intensity of heat in a heater, such as a top heater of an electric range. The actuator or knob 28 may be turned from the off position, to rotate the shaft 24, and rotate the cam construction 90, FIGURE 2, in a manner to adjust the various parts of the switch means inside the casing 76 to produce a gradually varying heat intensity from the off position along the numbers 1, 2, 3, 4, 5, 6 of the knob 28, to a maximum at the high position at the H1 or high position. A switch of this character, without the features of this invention, 18 manufactured and sold by the Robertshaw Controls Company and has been known for several years as an infinite switch. Further description of the switch means inside the casing 76 is therefore believed to be unnecessary.

The cam 90 is rotatable by the shaft 24 in any desired manner. Also, the cam 90 may have bearing extensions 92 and 94 which rotate in bearing openings in the bottom of casing 76 and in an insulative plate 96, which openings surround the bearings 92 and 94. The upper bearing 94 rotates in an opening in the insulative plate 96, which is held in shoulder means 98 along the sides of the casing 76.

The front switch casing panel 84 has fastening clips 100 which hold the front panel 84 from upward movement, as the tongues of the clips 100 engage the shoulders 102 at the sides of the casing 76. This is well known construction in the said switch of the Robertshaw Controls Company. The front of the panel 84 may have locating tongues or protrusions 104 which may extend into locating slots 106 in the range panel 82.

Other means may be provided for spacing the casing 76 from the panel 82, in a well known manner, which can be used in connection with this invention, but need not here be further described. In general, it may include brackets which permit the casing 76 to be spaced downwardly, in FIGURE 2, from the panel 82.

The shafts 24 and 68 may have a locating flange 108, which may be a true circular flange coaxial with the lower and cylindrical body 110. The body 110 is tightly clamped in the cam 90 by the flange 108 at the upper part of casing 76, and by a clamping plate 112, which is countersunk in a similarly shaped channel 114 in the bearing 92. The end of the shaft body 1'10 of shafts 24 and 68 originally has a narrower tubular extension 115, FIGURE 11, which is upset at 116, FIGURE 2, to secure the lower end of the shafts 24 and 68 tightly against the lower bearing 92 of the cam 90.

The shafts 24 and 68, the cylindrical body 110, the clamp 112, and the upsetting construction 116 may be produced and preassembled at the factory, so that the structure shown in FIGURE 1, including the casing 76, shaft 24 and bushing 78, etc., are all preassembled at the factory, and any proper connector 30 and the like may be placed over the end of the shafts either at the extreme end, as illustrated in FIGURE 1, or at any place along the fracture grooves 60, where the shafts may be fractured off to produce varying lengths of the shaft, and varying distances of the connector 30 from the casing 76. The connectors for D-shaped shaft 24 will all have near tubular ends as shown in FIGURES 6-9, whereas the connectors for square shaft 68 will all have square internal tubular near ends, as shown in FIGURE 10. The

6 far ends of the connectors may be the same for both shafts 24 and 68.

The bushing 78 may have a hexagonal flange 118 at its bottom end, which rests on the insulative plate 96. The front panel 84 has two slots 120, FIGURE 5B, which have downward flanges 122, FIGURE 5, which engage the straight sides 124 of the bushing flange 118. This construction holds the flange 118 against rotation, to hold the bushing 78 in place and against rotation.

The intermediate portion 126 of the shaft 24 (or 68) is made much smaller in diameter or lateral extent than the interior of the bushing 78, so that the tubular near end 32 of the connector 30 may be telescoped into the bushing 78, as shown in FIGURE 3, with its near end substantially against the cylindrical flange 108. This provides an advantage, in that the actuator or knob 28, of FIGURE 3, can be located very near the range panel 82, of FIGURE 2.

There are several well known shapes for the openings in actuators or knobs frequently used, in certain 10- calities, in connection with a switch of this character. In view of this, a plurality of connectors 30A, 30B, 30C, and 30D, FIGURES 13-16, may be provided, in addition to the connector 30 shown in FIGURES 1-9. These connectors 30, and 30A to 30D inclusive, may have their near ends 32, of FIGURES 6-9 and 32A, 32B, 32C, and 32D, of FIGURES 13-16, shaped to accept either the shaft 24, or the shaft 68 as desired. The far ends 36, 36A, 36B, 36C, and 36D, may be shaped to telescope into any of the well known openings of actuators which are commonly used in any locality in connection with a switch of this character.

In view of this, if desired, a replacement kit may be made, which will include the switch construction in the casing 76, and shaft 24 preassembled as previously described, and a collection of four or five connectors, more or less, such as 30, and 30A-30D. With this kit it is possible to remove a previous switch construction which may be mounted on a range panel or the like, with a specially tailored actuator or knob. The previous switch casing, shaft and actuator may be removed from the range panel, and then the replacement switch means or casing 76, with the shaft 24 (or shaft 70 as the case may be) may be placed or positioned in the same place as the previous switch on the range panel. Thereafter, the proper connector 30, or 30A30D may be selected, and may be placed over the shaft 24 or 68. In the particular illustration shown, the shaft 24 might be broken off half way toward the casing 76, and then the previously used actuator or knob 28 may be placed over the selected connector. This permits the previous knob to be retained on the range. The old knob is generally used because it may be diflflcult to find a new specially tailored knob.

The kit of this invention is much more simple, and much cheaper, than previous constructions where it was desired to replace an undesirable original installation and yet retain the original knob.

The previous kits included a switch in a casing, a plurality of shafts, a cam driver that had to be tightened with a small Allen wrench, a locating ring, etc. These shafts were much more expensive than applicants connectors. Applicants kit does not require the cam driver, the shafts, the Allen wrench and locating ring of the previous kit. Also, applicants method of assembly and replacement are much more simple.

It can be readily seen that the previous kit was very much more complicated, required much more labor at the place of installation, and had a larger number of expensive throw away unselected parts, as compared to the five relatively simple connectors 30, and 30A30D, which can be easily slipped over the shaft 24, or 68, as the case may be, at very little cost of installation and replacement.

It is thus to be seen that a new, useful and unobvious switch construction has been provided. Such switch construction may be used for original equipment, or may he used as the basis of a replacement kit which is much less expensive in original cost and in labor charges for replacement installation.

Also, the rotational axes of the cam 90,. the body 110, the shaft 24 or 68, the connectors 30 and 30A-30D and the actuator or knob 28 may all be made coaxial. This is made possible particularly by the construction of the connectors. This permits the knob 23 to rotate coaxially with the rotational axis of the cam 90 in an advantageous manner.

The switch construction of this invention has many other advantages both as original equipment and as re placement construction.

While the form of the invention now preferred has been disclosed as required by statute, other forms may be used, all coming within the scope of the claimed subject matter which follows.

What is claimed is:

1. In combination, a switch means, a rotatable operating shaft with a far shaft end, connected to said switch means, an integral plastic connector having a frictional tubular near connector end with an inner tubular surface frictionally telescoped over said far shaft end, and having a far connector end with an outer surface frictionally to be telescoped within a connector receiving manipulator opening of a switch manipulator and in which said far shaft end has fracture formation means to remove a portion of said shaft end and vary the length of said shaft.

2. A method of replacing a switch and its operating shaft, and retaining the original switch manipulator which has a switch actuating opening, which method comprises:

removing said switch, operating shaft and manipulator from its original operating location;

mounting a new switch with a preassembled operating shaft at said original location, with said shaft having a connector receiving shaft end;

telescoping the near end of a homogeneous, plastic,

elongated connector over said shaft end;

telescoping the far end of said connector into said manipulator opening in said original switch manipulator and in which said connector is removed from a plurality of different connectors and used because its near end has the proper shaft end telescoping re quirements to telescope on said preassembled shaft, and its far end has the proper actuating opening telescoping requirements to telescope into said switch actuating opening of said original switch manipulator and in which said preassembled shaft is shortened by removing a portion of said shaft end to permit said original switch actuator to occupy substantially its original operating location.

3. A method according to claim 2 in which said new switch is provided with a protruding bushing, and said near end of said connector is telescoped into said protruding bushing.

References Cited UNITED STATES PATENTS 949,504 2/ 1910 Sexton 2872 1,903,457 4/1933 Holstein. 2,143,401 1/1939 Arvin. 2,197,140 4/1940 Arvin 74--553 2,799,170 7/1957 Davis 74-504 2,908,150 10/1959 Stern 641 1 3,218,425 11/1965 Olenick et a1. 200168 2,912,527 11/1959 Nairner 200-6 3,226,519 12/1965 Garmendia 200166 FRED C. MATTERN, 18., Primary Examiner.

F. D. SHOEMAKER, Assistant Examiner.

. US. Cl. X.R. 200-168; 28753 

